Improvement in the valves of steam-engines



HUBBELL, OF CHARLES TOWN, MASSACHUSETTS.

IMPROVEMENT :N THE VALVES oF STEAM-ENGINES. i Y

Specification forming part of Letters Patent No. 42,327, dated April 12,1864.

To all whom it may concern.-

Be it known that I, GEORGE F. BLAKE, of Medford, in the county ofMiddlesex and State of Massachusetts, have invented an ImprovedSteam-Enginerand I do hereby declare the following to be a fullandcorrect description of the same, reference being had to theaceompanying drawings, in which y Figure 1 is a perspective view of' thelower or lmain cylinder with one of its heads removed, showing thesteam-chest, tappet-va/lve, and a portion ot' the ports. Fig. 2 is avertical transverse section of the engine through line m a: of Fig. 3.Fig. 3 is a longitudinal vereal section of the engine, showing theposition of the parts when the piston is at the end of .the forwardstroke. Fi g. 4. is a similar section,

showing the position of the parts when the piston is at the end of itsrearward stroke. Fig-5 is a perspective view of the steamchest, thetappet-valve being removed and all the ports shown. Fig. 6 is aperspective view of one end of the upper cylinder with its head removed.Fig. 7 is a view of one head ot' the upper cylinder; Figs. 8 and 9, backand front views of the tappet-valve; Fig. 10, a view of the slide-valve;Fig. 11, a perspective view of the plunger that works in the uppercylinder.

The nature of this invention consists in the arrangement andconstruction, hereinafter particularly described, of a Steamengine, inwhich an auxiliary cylinder is employed to operate the valves of themain cylinder, the valves of said auxiliary cylinders being operateddirec'ly by the Vpiston of the main cylinder. By' this construction anengine is obtained which is compact, simple,little liable to get ont oforder, easily taken apart for repair, and admirably adapted for/pumpingor other purpose, where it is desirable to have but a small spacebetween the engine and the machinery which itis to operate, all ashereinafter more fully set forth.

To enable others skilled in the art to make. and use my improved engine,I will proceed to describe its construction and operation, referring tothe drawings, wherein the same part is marked by the same letter ofreference wherever it occurs.

Amarins the main cylinder, which is of the usual form, having flanges Bcnits ends, to i off the exhaust. cut-ting oii of ghe ex .i

which the cylinderheads G C are secured .by bolts in the ordinary way.

D is tlle piston, and Ethe'piston-rod. The

. piston D, as it approaches the end either of its forward or backwardstroke comes in contact with the tappets tt ofthe tappetvalve shown inFigs. 8 and 9, and its position in the l steamehest G is shown in Fig. 1in view. and in Figs. 2,3, and 4, in section. controls the'stea-m-portsg h ij, which regulate the supply and exhaust of the upper cylinder. Theports g and h convey steam t0 and from the Vends of the cylinder K tothe valve. The ports and j communicate with the exhaust. Thetappet-va-lve is operated by, the piston D, which strikes vone of itstappets at the end of each stroke.

G is the steam-chest, which receives steam from the engine through theinlet-portf. The supply and exhaust of the main cylinder are controlledby the silde-valve H, which is operated by the plunger J of the uppercylinder, K, to lwhich it is connected' by the stem I.

The ports a and b lead from the valve H to either end of the cylinder A.The ports d and e lead from the steamchest G to the valve H. The port cis the common exhaust for bothV ends of cylinder A. The plunger J is ahol- .low cylinder with solid ends, and is 4clearly represented inperspective .view in Fig. l1 and in t1 ausverse and longitudinal sectionin Figs. 2, 3, and 4. It has large openings inits sides, as shown, andtwo ports, lc 7c', which open into cavities l near the ends, and on theinterior of' cylinder K. (See Figs. 3, 4 and 6.) The heads L M ot thecylinder K have small steamways m m (sce Figs. 3, 4, and 7)communicating with steam-ways. y and h, and 'each covered by aspring-valve, n. This valve is shown in Fig. 7 pushed to one side touncover the opening of the passage. The object of the passages 7.1 l isto. admit steam be'- yond the ends of the plungerJ in orderto arrest itsmotion. These ports k ldo not take steam until the plunger J has passedand cut Thisv valve haust by the plunger forms a .deadpoint, to

overcome whichI admit steam from the ways g and hthrough the passage m,controlled by the springvalve n, which closes when its end of thecylinder exhausts and opens when the supply-port is again opened.

The operation has been partly indicated in 'the foregoing description of,the construction of the engine. The position of the parts when thepiston is at the forward end of its' stroke j is shown in Fig. 3. Theslide-valve H is driven forward to the end of its stroke in that" -whatI claim-therein as new, and desire to sedireotion, and the rearward endof the cylinder is then open to the exhaustthrough ways' band c, andsteam passs from the steamlchest through ways d and a 'into the forwardendv of thecylinder .and drives back the piston D tothe positionvsliownin Fig.

4which exhibits the relations ofthe parts when' the piston has reachedthe end of its yrearward stroke.l The slidevalve H is. then driven backto the end of its stroke in that direction, 'and theway to the exhaustis openI from the forward end of thel cylinder through .passages-a. andc while steam enters the rearend 'of the4 cylinder through'wa-yse'an'db.' .Lhe slide valve.' H; is operated by the -K plunger J, `theports which control Athe move ments of said plunger being operated bythe proaches'the end ot' its forward stroke, it strikes theltappet t 'ofthe yalve F and ,drivesv that yalve' forward to the end of its stroke inthat direction. When the valveil? is in that po-l sition, the forwardendof the upper cylinder,

K, 'exhausts through ways grand t', whilethe rearward end takes steamthrough h. When 'piston D reaches" the rearward end of its p stroke,`itstrikesfthe tappet t of valve F,

and drivesthat valve to .therearward end ot' end toward which it is`travelin g through ports la l, for the purpose of cushioning the end ofthe plunger. 'lhe passage of the plunger beyond the exhaust would form,as before mentioned, a dead-point; but when steam is again 'admitted tothe way leading to that -end of the 'cylinder itpasses round throughpassage m and opens spring-valve n and starts the plunger on itsVreturnstroke. The spring-valve 'n closes during the exhaust by theforce` of its own elasticity. 1

` Having thus fully described my invention,

cure by Letters. Patent, is-' l 1. Thev combination and arrangement ofthe cylinder A, tapp'et-valve F, 'slide-valve H,

with'their seats lin the s team-chest Gr, plunger' receives its motionfrom the direct action of' the piston. of the main cylinder withouttheintervention of. intermediate parts, when the ports of the main cylinderare controlled by,

means ot-a slidevalve attached to andoperated by the plunger oftheauxiliary cylinder,

substantiallyY in' the manner set forth.

3. Thear'rangement of the steam-ports onv valve-seats placed at rightangles to eachother, 4 so as to allow of thef'working of'` two,independent valves within'the stea'l'n-chest, in the manner andfbr'the'purposeispecilied j 4. IThe combination of the `ports lc k' withvthe ways H', for thevpurpose ot' cushioning the plunger J after it hasout off the exhaust,

in the manner described.

, '5. The 'steamways m..m, in combination with the spring-valves n n,arrangedl and op eratingv in' the manner and for .the purpose specified.

The.'above specification ofmy said in'venl tion signed and witnessed, atBoston, this 6th day of February, A. 1864' GEORGE FQB'LAKE.

Witnesses:

B. E. PERRY, SUMNER ALB EE.

